Distribute FunctionSymbol over Object Arrays

Mostly to fix the norm for arrays. Before it wasn't summing up the components.

grudge/symbolic/primitives.py

@@ -362,6 +362,16 @@ class FunctionSymbol(ExpressionBase, VariableBase):
     :class:`~pymbolic.primitives.Call`.
     """
 
+    def __call__(self, expr):
+        from pytools.obj_array import is_obj_array
+
+        if is_obj_array(expr):
+            from pytools.obj_array import with_object_array_or_scalar
+            return with_object_array_or_scalar(
+                    super(FunctionSymbol, self).__call__, expr)
+
+        return super(FunctionSymbol, self).__call__(expr)
+
     mapper_method = "map_function_symbol"